Improvement in furnaces for smelting lead



l. V. WUODHOUSE.

Furnace for smelting Lead.

Patented Oct. 5,1875.

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N. PETERS, PNOTO-LITHOGRAPHER, WASHINGTON. D O.

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UNITED STATES PATENT OFFICE.

JOHN V. WOODHOUSE, OF BUNKER HILL, ILLINOIS.

IMPROVEMENT IN FURN ACES FOR SMELTING LEAD.

/ Specification forming part of Letters Patent No. 168,440., datedOctober 5, 1875; application filed June 7, 1875.

To all whom it may concern:

Be it known that I, JOHN V. WooDHoUsE, late of Mine La Motte, Missouri,but now of Bunker Hill, Illinois, have invented new and usefulImprovements in Furnaces for Smeltin g Lead, of which the following is afull, clear, and exact description, reference being had to the annexeddrawing, making part of this specification, in which-- Figure 1 is acentral cross-sectional elevation; Fig. 2, a front elevation; Fig. 3, ahorizontal section on the line y y of Fig. 2, and Fig. 4 a horizontalsection on the line 00 m of Fig. 2.

Like letters indicate like parts.

In smelting lead ores in the ordinary Scotch or American hearth thewalls thereof soon heat to such an extent as to cause the metal tofreeze (a smelters term) thereto.

To obviate this it has been customary to cease smelting until the wallshave cooled.

To provide for continuous smelting I have previously made an improvementwherein the hearth-walls are made hollow, and a circulation of watercaused therein. By this means the walls can be cooled, but an incrus'tation (especially where limy water is used) is apt to form, whichoccasions cracks, terminatin g the usefulness of the construction.

It is the aim of the present invention to provide for maintaining theproper temperature in a lead-smelting furnace, and in such manner as toavoid injury thereto. The invention also relates to the shape of thefurnace and the arrangement of its tuyeres.

Referring to the accompanying drawing, A represents the furnace-wall. Asshown at B, Figs. 1, 3, and 4, it is made hollow to form an air-chamber,to which is an inlet, 1), and an outlet, b. This air-chamber extendsthroughout the wall, and is entirely distinct from another air-chamber,O, which is arranged in the rear and at the bottom of the wall. To thislast-named chamber is an in- D D D D D represent a series of tuyeresleading from the chamber 0 to the hearth E. The wall A of the furnace ismade semicircular, as shown, and the tuyeres .are distributed not onlyat the back of the furnace, but around at either side.

In the construction seen that two distinct air-circulating systems areprovided for-one to furnish means for the free circulation of cool airthroughout the furnace-wall, and the other to provide a blast to feedthe combustion inside the furnace. If preferred, both these blasts canbe supplied by a common blower, the proper diversion being made so thatthe air can enter partly at the inlet 12 and partly at the inlet 0.

In operation, an air-blast is sent through the chamber B, cooling thefurnace-wall to the desired point, and without causing any injurythereto. Another blast is directed through the chamber 0 into the fire.It is desirable that this last-named blast be not heated before enteringthe furnace, as in the smelting of lead there is a continual liabilityto overheating.

It will be seen that by the construction described the cooling air-blastcan be utilized in keeping down the temperature of the tuyeres throughwhich the other blast is entering. It will also be noticed that the wallof the present furnace is made in a horseshoe form. Hitherto this wallhas been built in a rectangular form, from which construction there havebeen corners in the furnaces in which the ores were cooler than in themore central parts of the furnace. In consequence the smelting proceededirregularly;

, To obviate this difiiculty I construct the walls as described, andalso distribute the tuyeres, as shown, and so as to secure an evenheating. By this means the smelting proceeds evenly throughout thefurnace.

I am aware that, in smelting lead in a blast-furnace, the blast used inmaintaining combustion has been heated previously to its admission to.the fire. I am also aware that in a reverberatory furnace an air-currenthas been drawn through its hearth, (which is hollow,) and thence intothe furnace. As the result of such methods is the increasing of thetemperature of the furnace to such a degree as to prevent continuoussmelting, they, even if new with me, would not answer my presentpurpose. and I disclaim them; but

Having described my invention, what I claim as new therein, and desireto secure by described it will be Letters Patent, is-

1 The semicircular wall A, provided with circular Wall and the tuyeres DD D D D, arthe air-chamber B, the chamber 0, tuyeres D ranged asdescribed, as and for the purpose 1) D D D, arranged as described, andhearth set forth., E, substantially as described.

2. The hearth E, provided with the semi JOHN WOODHOUSE' circular wall A,as and for the purpose set Witnesses: forth. 7 OHAs. D. Moomz,

3. The hearth E, provided with the semi- DANL. T, POTTER.

